[codex] Add copy button for rendered code blocks

desktop/scripts/check-file-sizes.mjs

@@ -40,7 +40,7 @@ const overrides = new Map([
   ["src/features/channels/ui/ChannelScreen.tsx", 550], // profile panel state + mutual exclusion wiring + ProfilePanelProvider context + agent typing classification
   ["src/features/notifications/hooks.ts", 535], // notification settings + feed notification lifecycle + profile batch resolution + truncated-pubkey guard + badge state
   ["src/features/messages/hooks.ts", 500], // message query/mutation hooks + optimistic updates
-  ["src/features/messages/ui/MessageComposer.tsx", 710], // media upload handlers (paste, drop, dialog) + channelId reset effect + edit mode (pre-fill, save, cancel, escape) + composer autofocus (#572)
+  ["src/features/messages/ui/MessageComposer.tsx", 760], // media upload handlers (paste, drop, dialog) + channelId reset effect + edit mode (pre-fill, save, cancel, escape) + composer autofocus (#572) + Sprout code-block paste branch (round-trips copy-button output as a literal codeBlock so Markdown can't reshape it) + scroll-to-bottom on multi-line paste (#619)
   ["src/features/settings/ui/SettingsView.tsx", 600],
   ["src/features/sidebar/ui/AppSidebar.tsx", 860], // channels + forums creation forms + Pulse nav
   ["src/shared/api/relayClientSession.ts", 930], // durable websocket session manager with reconnect/replay/recovery state + sendTypingIndicator + fetchChannelHistoryBefore + subscribeToChannelLive (huddle TTS) + subscribeToHuddleEvents (huddle indicator) + disconnect() for workspace switch teardown + fetchEvents/subscribeLive/publishEvent for NIP-RS read state + publishUserStatus/subscribeToUserStatusUpdates (NIP-38)

desktop/src/features/messages/ui/MessageComposer.tsx

@@ -21,6 +21,7 @@ import {
 } from "@/features/messages/lib/normalizeMentionClipboard";
 import { useRichTextEditor } from "@/features/messages/lib/useRichTextEditor";
 import { useTypingBroadcast } from "@/features/messages/useTypingBroadcast";
+import { getSproutCodeBlockClipboardText } from "@/shared/lib/codeBlockClipboard";
 import { cn } from "@/shared/lib/cn";
 import { Button } from "@/shared/ui/button";
 import { ChannelAutocomplete } from "./ChannelAutocomplete";
@@ -134,6 +135,15 @@ export function MessageComposer({
     emojiAutocomplete.isEmojiAutocompleteOpen;
 
   const submitMessageRef = React.useRef<() => void>(() => {});
+  const composerScrollRef = React.useRef<HTMLDivElement>(null);
+
+  const scrollComposerToBottom = React.useCallback(() => {
+    window.requestAnimationFrame(() => {
+      const scrollElement = composerScrollRef.current;
+      if (!scrollElement) return;
+      scrollElement.scrollTop = scrollElement.scrollHeight;
+    });
+  }, []);
 
   const computedPlaceholder = editTarget
     ? "Edit your message"
@@ -498,6 +508,33 @@ export function MessageComposer({
             return true;
           }
 
+          // --- Sprout code-block paste ---
+          // The code block copy button writes a small Sprout marker alongside
+          // plain text. Use it to paste back as a literal code block so Markdown
+          // parsing cannot reshape indentation, fence markers, or headings.
+          const codeBlockText = getSproutCodeBlockClipboardText(
+            event.clipboardData,
+          );
+          if (codeBlockText !== null) {
+            event.preventDefault();
+            richText.editor
+              ?.chain()
+              .focus()
+              .insertContent([
+                {
+                  type: "codeBlock",
+                  content:
+                    codeBlockText.length > 0
+                      ? [{ type: "text", text: codeBlockText }]
+                      : [],
+                },
+                { type: "paragraph" },
+              ])
+              .run();
+            scrollComposerToBottom();
+            return true;
+          }
+
           // --- Mention / channel-link normalization ---
           // When copying from the chat area the browser puts styled HTML
           // on the clipboard. TipTap's DOMParser doesn't understand our
@@ -524,11 +561,16 @@ export function MessageComposer({
             return true;
           }
 
+          const plainText = event.clipboardData?.getData("text/plain") ?? "";
+          if (plainText.includes("\n")) {
+            scrollComposerToBottom();
+          }
+
           return false;
         },
       },
     });
-  }, [richText.editor]);
+  }, [richText.editor, scrollComposerToBottom]);
 
   // ── Send button state ───────────────────────────────────────────────
   const sendDisabled = React.useMemo(
@@ -673,6 +715,8 @@ export function MessageComposer({
           {/* biome-ignore lint/a11y/noStaticElementInteractions: keydown handler bridges Tiptap editor to autocomplete and submit */}
           <div
             className="rich-text-composer max-h-32 overflow-y-auto"
+            data-testid="message-input-scroll"
+            ref={composerScrollRef}
             onKeyDown={handleEditorKeyDown}
           >
             <EditorContent editor={richText.editor} />

desktop/src/shared/lib/codeBlockClipboard.ts

@@ -0,0 +1,57 @@
+const SPROUT_CODE_BLOCK_ATTRIBUTE = "data-sprout-code-block";
+
+function escapeHtml(value: string) {
+  return value
+    .replace(/&/g, "&")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/"/g, "&quot;");
+}
+
+function createSproutCodeBlockHtml(code: string) {
+  // Keep the code as one text node; the paste reader recovers it via textContent.
+  return `<pre ${SPROUT_CODE_BLOCK_ATTRIBUTE}="true"><code>${escapeHtml(code)}</code></pre>`;
+}
+
+export async function copyCodeBlockToClipboard(code: string) {
+  const clipboard = navigator.clipboard;
+  if (!clipboard) {
+    throw new Error("Clipboard API is unavailable");
+  }
+
+  if (
+    typeof ClipboardItem !== "undefined" &&
+    typeof clipboard.write === "function"
+  ) {
+    try {
+      await clipboard.write([
+        new ClipboardItem({
+          "text/html": new Blob([createSproutCodeBlockHtml(code)], {
+            type: "text/html",
+          }),
+          "text/plain": new Blob([code], { type: "text/plain" }),
+        }),
+      ]);
+      return;
+    } catch (error) {
+      console.warn("Failed to write rich code block clipboard data", error);
+    }
+  }
+
+  await clipboard.writeText(code);
+}
+
+export function getSproutCodeBlockClipboardText(
+  clipboardData: DataTransfer | null | undefined,
+) {
+  const html = clipboardData?.getData("text/html");
+  if (!html?.includes(SPROUT_CODE_BLOCK_ATTRIBUTE)) {
+    return null;
+  }
+
+  const document = new DOMParser().parseFromString(html, "text/html");
+  const code = document.querySelector(`[${SPROUT_CODE_BLOCK_ATTRIBUTE}] code`);
+  const fallback = document.querySelector(`[${SPROUT_CODE_BLOCK_ATTRIBUTE}]`);
+
+  return code?.textContent ?? fallback?.textContent ?? null;
+}

desktop/src/shared/ui/markdown.tsx

@@ -1,22 +1,25 @@
 import * as React from "react";
 import ReactMarkdown, { type Components } from "react-markdown";
 import * as DialogPrimitive from "@radix-ui/react-dialog";
+import { Copy } from "lucide-react";
 import remarkBreaks from "remark-breaks";
 import remarkGfm from "remark-gfm";
-
 import { toast } from "sonner";
 
 import { useAppNavigation } from "@/app/navigation/useAppNavigation";
 import { UserProfilePopover } from "@/features/profile/ui/UserProfilePopover";
 import { invokeTauri } from "@/shared/api/tauri";
 import type { Channel } from "@/shared/api/types";
 import { useChannelNavigation } from "@/shared/context/ChannelNavigationContext";
+import { copyCodeBlockToClipboard } from "@/shared/lib/codeBlockClipboard";
 import { cn } from "@/shared/lib/cn";
 import { rewriteRelayUrl } from "@/shared/lib/mediaUrl";
 import rehypeImageGallery from "@/shared/lib/rehypeImageGallery";
 import rehypeSearchHighlight from "@/shared/lib/rehypeSearchHighlight";
 import remarkChannelLinks from "@/shared/lib/remarkChannelLinks";
 import remarkMentions from "@/shared/lib/remarkMentions";
+import { Button } from "@/shared/ui/button";
+import { Tooltip, TooltipContent, TooltipTrigger } from "@/shared/ui/tooltip";
 
 import {
   classifyChildren,
@@ -103,6 +106,75 @@ function ImageContextMenu({
   );
 }
 
+function getReactNodeText(node: React.ReactNode): string {
+  if (typeof node === "string" || typeof node === "number") {
+    return String(node);
+  }
+
+  if (Array.isArray(node)) {
+    return node.map(getReactNodeText).join("");
+  }
+
+  if (React.isValidElement<{ children?: React.ReactNode }>(node)) {
+    return getReactNodeText(node.props.children);
+  }
+
+  return "";
+}
+
+function getCodeBlockText(children: React.ReactNode) {
+  return getReactNodeText(children).replace(/\n$/, "");
+}
+
+function MarkdownCodeBlock({ children }: { children?: React.ReactNode }) {
+  const [isCopying, setIsCopying] = React.useState(false);
+  const code = React.useMemo(() => getCodeBlockText(children), [children]);
+
+  const handleCopy = React.useCallback(
+    async (event: React.MouseEvent<HTMLButtonElement>) => {
+      event.preventDefault();
+      event.stopPropagation();
+      setIsCopying(true);
+
+      try {
+        await copyCodeBlockToClipboard(code);
+        toast.success("Copied code to clipboard");
+      } catch (error) {
+        console.error("Failed to copy code block", error);
+        toast.error("Failed to copy code");
+      } finally {
+        setIsCopying(false);
+      }
+    },
+    [code],
+  );
+
+  return (
+    <div className="group relative">
+      <pre className="overflow-x-auto rounded-xl border border-border/70 bg-muted/60 px-3 py-1.5 pr-12 shadow-sm">
+        {children}
+      </pre>
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <Button
+            aria-label="Copy code block"
+            className="absolute right-2 top-2 h-7 w-7 bg-background/80 text-muted-foreground opacity-0 shadow-sm ring-1 ring-border/60 backdrop-blur transition-opacity hover:bg-background hover:text-foreground hover:opacity-100 focus-visible:opacity-100 group-hover:opacity-100 group-focus-within:opacity-100 disabled:opacity-60"
+            disabled={isCopying}
+            onClick={handleCopy}
+            size="icon"
+            type="button"
+            variant="ghost"
+          >
+            <Copy className="h-3.5 w-3.5" />
+            <span className="sr-only">Copy code block</span>
+          </Button>
+        </TooltipTrigger>
+        <TooltipContent>Copy code</TooltipContent>
+      </Tooltip>
+    </div>
+  );
+}
+
 function createMarkdownComponents(
   variant: MarkdownVariant,
   channels: Channel[],
@@ -141,18 +213,12 @@ function createMarkdownComponents(
       </blockquote>
     ),
     br: () => <br />,
-    code: ({
-      children,
-      className,
-      ...props
-    }: React.ComponentProps<"code"> & { inline?: boolean }) => {
+    code: ({ children, className, ...props }: React.ComponentProps<"code">) => {
       const code = String(children).replace(/\n$/, "");
-      const isBlock =
-        typeof className === "string" && className.includes("language-")
-          ? true
-          : code.includes("\n");
+      const isFencedCodeBlock =
+        typeof className === "string" && className.includes("language-");
 
-      if (isBlock) {
+      if (isFencedCodeBlock || code.includes("\n")) {
         return (
           <code
             {...props}
@@ -297,11 +363,7 @@ function createMarkdownComponents(
 
       return <p className={paragraphClassName}>{children}</p>;
     },
-    pre: ({ children }) => (
-      <pre className="overflow-x-auto rounded-xl border border-border/70 bg-muted/60 px-3 py-1.5 shadow-sm">
-        {children}
-      </pre>
-    ),
+    pre: ({ children }) => <MarkdownCodeBlock>{children}</MarkdownCodeBlock>,
     strong: ({ children }) => (
       <strong className="font-semibold">{children}</strong>
     ),

desktop/tests/e2e/messaging.spec.ts

@@ -49,6 +49,91 @@ test("send multiple messages in sequence", async ({ page }) => {
   }
 });
 
+test("copy a rendered code block and paste it back as code", async ({
+  page,
+}) => {
+  await page.context().grantPermissions(["clipboard-read", "clipboard-write"], {
+    origin: "http://127.0.0.1:4173",
+  });
+
+  const code = "# not a heading\nconst answer = 42;\n  indented();";
+
+  await page.goto("/");
+  await page.getByTestId("channel-general").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("general");
+
+  const input = page.getByTestId("message-input");
+  await page.evaluate(
+    (text) => navigator.clipboard.writeText(text),
+    `\`\`\`ts\n${code}\n\`\`\``,
+  );
+  await input.click();
+  await page.keyboard.press("ControlOrMeta+V");
+  await page.getByTestId("send-message").click();
+
+  const copiedCodeBlock = page.locator("pre", { hasText: code });
+  await expect(copiedCodeBlock).toHaveCount(1);
+
+  const copyButton = page.getByLabel("Copy code block");
+  await expect(copyButton).toHaveCSS("opacity", "0");
+  await copiedCodeBlock.hover();
+  await expect(copyButton).toHaveCSS("opacity", "1");
+  await copyButton.click();
+  await expect
+    .poll(() => page.evaluate(() => navigator.clipboard.readText()))
+    .toBe(code);
+
+  await input.click();
+  await page.keyboard.press("ControlOrMeta+V");
+  await input.press("Enter");
+
+  await expect(copiedCodeBlock).toHaveCount(2);
+});
+
+test("pasting a long copied code block scrolls composer to cursor", async ({
+  page,
+}) => {
+  await page.context().grantPermissions(["clipboard-read", "clipboard-write"], {
+    origin: "http://127.0.0.1:4173",
+  });
+
+  const longCode = Array.from(
+    { length: 48 },
+    (_, index) => `const line${index} = ${index};`,
+  ).join("\n");
+
+  await page.goto("/");
+  await page.getByTestId("channel-general").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("general");
+
+  const input = page.getByTestId("message-input");
+  await page.evaluate(
+    (text) => navigator.clipboard.writeText(text),
+    `\`\`\`ts\n${longCode}\n\`\`\``,
+  );
+  await input.click();
+  await page.keyboard.press("ControlOrMeta+V");
+  await page.getByTestId("send-message").click();
+
+  const copiedCodeBlock = page.locator("pre", { hasText: longCode });
+  await expect(copiedCodeBlock).toHaveCount(1);
+  await copiedCodeBlock.hover();
+  await page.getByLabel("Copy code block").click();
+
+  await input.fill("typed before paste");
+  await page.keyboard.press("ControlOrMeta+V");
+
+  const scrollContainer = page.getByTestId("message-input-scroll");
+  await expect
+    .poll(() =>
+      scrollContainer.evaluate(
+        (element) =>
+          element.scrollHeight - element.clientHeight - element.scrollTop,
+      ),
+    )
+    .toBeLessThanOrEqual(1);
+});
+
 test("message input clears after send", async ({ page }) => {
   const message = `Clear after send ${Date.now()}`;
   const input = page.getByTestId("message-input");